Hi @Guðjón ,
What’s the version of your Outlook 365(File>Office account>About Outlook)?
According to my tests, I can reproduce the same issue as you in my Outlook 365(Version 2007 Build 13029. 20344 Click-to-Run). As I know, the People pane feature in Outlook is usually related to the Outlook Social Connector. However, Outlook Social Connector is not available in Outlook for Office 365 or Outlook 2019. So, the People pane feature is no longer unavailable in newer versions of Outlook 365 desktop client.
Not all workstations are affected.
Do you mean that there are other Outlook 365 client which can use the People pane feature normally? If so, what’s the version of those specific Outlook client? To solve your issue, as a workaround, you could try to revert the version of your outlook so that you can use the People pane feature again.
Besides, If you still would like this feature in newer version of Outlook 365 client, you could post your feedback via Outlook UserVoice.
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